AS-Interface Slave IC

AS2702 (SAP4.1)

Rev. C, January 2001

Page 2 of 18

.H\ )HDWXUHV

• Interface Device to connect Actuators and Sensors to an AS-Interface Bus

• Conforms to AS-Interface Spec. V2.11

• DC Power Extraction from the AS-Interface Bus

• Serial bidir. Data Communication with the Bus

• Data Communication Watchdog

• 4-Bit bidir. Data Port plus Strobe to poll the Sensors and control the Actuators con-

nected

• 4-Bit Parameter Port plus Strobe to provide Settings to the Sensors and Actuators

• 24V Power Supply for the Sensors and Actuators

• Periphery Fault Input to signal Hardware Failure of the Sensors and Actuators

• Integrated 16 x 8 Bit EEPROM to store (5 + 1)-Bit Slave Address and Settings

• 2 LED Outputs to optically flag Slave Unit Operation Status

• Operating Temperature Ta:

- 25 °C … + 85 °C

• Operating Supply Voltage / Bus DC Voltage:

typ. 30 V

• Operating Current (Osc. on, Outputs idle):

≤ 6 mA

• Supply for Sensors / Actuators:

typ. 24 V,

≤ 50 mA

• Package:

SOIC 20 for full Functionality;

SOIC 16 for Applications not requiring the Parameter Port

*HQHUDO'HVFULSWLRQ

AS2702 (SAP4.1) is a new generation AS-interface slave device conforming to AS-interface-

specification V2.11, which supports AS-interface bus systems with up to 62 slave modules.

Each slave module is equipped with an AS2702 device, which interfaces the module to the

unshielded 2-wire AS-interface bus for serial bidirectional data communication and power ex-

traction.

Data communication over the AS-interface bus takes place in master slave fashion, which

foresees that all slave devices AS2702 connected to the bus are sequentially and cyclicly ad-

dressed by a single, central master unit. Data on the AS-interface bus are Manchester en-

coded and can be found as sin2-pulses with a Vpp of between 3V and 8V on top of the bus’

dc voltage of nominally 30V.

AS2702 regulates the nominal dc bus voltage of 30V internally down to 5V to supply it’s inter-

nal circuitry including a 16 x 8 bits EEPROM, as well as down to a nominal supply level 24V

with a max. loading of 50 mA for the actuators and sensors connected to it at the field side.

Each slave device AS2702 may interface to up to 4 sensors or 3 actuators. An AS-interface

bus system based on AS2702 may hence link as many as 248 sensors or 186 actuators to a

single master unit.

Slave device AS2702 (SAP4.1) is system compatible with predecessor device AS2701A

(ISA3+): slave modules equipped with AS2702 (SAP4.1) will run in existing AS-interface bus

systems based on AS2701A (ISA3+).

The AS-interface concept is well established as a standardized digital bus system for indus-

trial automation.